In adaptive array transmission conducted by a base station practically applied to PHS (Personal Handy-phone System) and XGP (eXtended Global Platform), control is exerted which conducts beamforming transmission toward a desired terminal to strengthen radio waves and conducts null steering transmission toward an interfering terminal to weaken radio waves (for example, refer to Patent Document 1 (Japanese Patent Laying-Open No. 2004-297276)).
Accordingly, improved frequency utilization efficiency is achieved. Application of such an adaptive array communication technique is being studied for TD-LTE (Long Term Evolution) and WiMAX (Worldwide Interoperability for Microwave Access).